Mounting for a stator blade adjusting cylinder on an axial compressor

ABSTRACT

The adjusting cylinder is mounted in the casing to move axially while radial movements are compensated for by allowing the cylinder to move radially relative to the casing in a controlled plane. The mounting includes a cylindrical guide rod in a bearing block on one side and a flat surfaced support bar in a support on the opposite side. The support bar is able to slide axially and radially of the casing within the support.

United States Patent [191 Benz [11] 3,829,234 [451 Aug. 13, 1974 MOUNTING FOR A STATOR BLADE ADJUSTING CYLINDER ON AN AXIAL COMPRESSOR [75] inventor: Hans Benz, Winterthur, Switzerland [73] Assignee: Brown Boveri-Sulzer Turbomachinery, Ltd., Zurich, Switzerland 22 Filed: July 3,1973 21 Appl.No.:376,165

[30] Foreign Application Priority Data July 13, 1972 Switzerland 10516 [52] US. (I! 415/138, 415/219 R, 248/19, 248/DIG. 1

[51] Int. Cl. F04d 29/52, Fl6m 9/00 [58] Field of Search 248/19, 55, DIG. 1; 415/108, 219,136,138

[56] References Cited UNITED STATES PATENTS 1,067,356 7/1913 Ljungstrom 415/136 2,823,890 2/1958 Oechslin 415/136 3,0669! 1 12/1962 Anderson et a1. 3,628,884 12/1971 Mierley, Sr. 415/219 R FOREIGN PATENTS OR APPLICATIONS 107,625 6/1943 Sweden 415/219 R 369,680 3/1932 Great Britain 415/138 Primary Examiner--Henry F. Raduazo Attorney, Agent, or FirmKenyon & Kenyon Reilly Carr & Chapin 5 7 ABSTRACT The adjusting cylinder is mounted in the casing to move axially while radial movements are compensated for by allowing the cylinder to move radially relative to the casing in a controlled plane. The mounting includes a cylindrical guide rod in a bearing block on one side and a flat surfaced support bar in a support on the opposite side. The support bar is able to slide axially and radially of the casing within the support.

5 Claims, 2 Drawing Figures MOUNTING FOR A STATOR BLADE ADJUSTING CYLINDER ON AN AXIAL CUWRIESSOR This invention relates to a mounting for a stator blade adjusting cylinder of an axial compressor.

As is known, the stator blades of an axial compressor have been secured to adjusting cylinders which are slidably mounted in a casing of the compressor. Generally, the cylinders have been disposed coaxially with the stator blade support and have supported slotted rings into which adjusting levers of the individual stator blades engage. Adjustment of the blades in such a construction has been obtained by axial displacement of the cylinder in the casing of the compressor. i

However, the support of the cylinder in the casing frequently gives rise to difficulties owing to different thermal expansions between the adjusting cylinder and the casing. Since the cylinder is usually subject to greater elongation than the casing, particularly in the radial direction, the cylinder must be movable with respect to the casing both axially, because of the axial displacement required for adjusting the blades, and radially.

Accordingly, it is an object of the invention to provide a simple and efficient support for a stator blade adjusting cylinder in which the necessary movability in both axial and radial directions is ensured.

Briefly, the invention provides a means for mounting an adjusting cylinder within a casing of an axial compressor in which the cylinder is mounted on two opposite sides to move axially relative to the casing as well as radially from a fixed longitudinal axis on one side. The mounting means includes at least one cylindrical guide rod secured to one of the casing and cylinder to one side of the cylinder and a bearing block secured to the other of the casing and cylinder and slidably receiving the guide rod. The guide rod is disposed axially of the casing to slide within the bearing block axially of the casing along a fixed longitudinal axis. In addition, the mounting means includes at least one support bar secured to one of the casing and cylinder to the opposite side of the casing from the guide rod as well as a support secured to the other of the casing and cylinder. The support bar is also disposed axially of the casing and slides within the support not only axially of the casing but also radially of the casing in a plane passing through the fixed longitudinal axis defined by the guide rod.

The cylindrical guide rod or rods on one longitudinal side together with their bearing blocks represent a fixed point for radial motions while permitting movability in the axial direction. The support or supports which are provided on the other longitudinal side permit the support bars and therefore the adjusting cylinder to permit axial displacements and radial elongations with respect to the casing.

The support for each support bar includes a support block on which a support bar can slide as well as a retaining member which is removably secured on the support block to prevent the support bar from lifting off the support block. In this way, rotating movements of the casing about the fixed longitudinal axis of the guide bar or bars is prevented.

In order to reduce the frictional resistance to axial displacement, the sliding surfaces of the bearing blocks, of the supports and, in some circumstances of the retaining members, are constructed of selflubricating bearing material.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 diagrammatically illustrates a plan view of an axial compressor with adjusting cylinders supported by a mounting means according to the invention and with the upper half of the compressor casing, which is divided in a horizontal axial plane, removed; and

FIG. 2 illustrates a view taken along the line II-II of FIG. 1.

Referring to FIG. I, the axial compressor includes a casing l of tubular construction in which an adjusting cylinder 7 of two-piece construction is mounted. As shown, the two pieces of the cylinder 7 are of different diameters.

Referring to FIGS. 1 and 2, brackets 2 are welded into or integrally cast on to the interior of the casing 1 at diametrically opposite sides. In order to mount the cylinder 7 in the casing I, a plurality of mounting means are provided along the length of the casing 1.

Each mounting means includes a bearing block 3 which is secured to one bracket 2 by means of a threaded bolt 6 and a cylindrical guide rod 8 which is secured at the ends, as by welding, in an end flange 10 on the cylinder 7 and in a lug 11 welded to the outside of the cylinder 7 (FIG. 1). The guide rod 8 is disposed axially of the casing l to slide within the bearing block Each mounting means also includes a support 4 (FIG. 2) mounted on an opposed bracket 2. Each support 4 includes a fiat support block and a retaining member 5 which are secured by a bolt 6 to the bracket 2. In addition, a support bar 9 is secured at the ends, as by welding, to a flange 10 and a lug 11 on the cylinder 7 (FIG. 1) and is provided with two oppositely disposed fiat surfaces (FIG. 2) which bear against flat bearing surfaces of the support 4. The fiat support bar surfaces can be produced by cutting off two diammetrically opposed cylindrical circular sections from a guide rod 8 in order to simplify manufacture and storekeeping.

Both the guide rods 8 and the support bars 9 are constructed of steel.

As shown in FIG. 1, the cylinder 7 is also provided with two projections 12 which extend outwardly through the casing l to cooperate with servomotors (not shown) in order to effect an axial sliding of the cylinder 7 relative to the casing 1.

As shown in FIG. 2, the guide rods 8 and support bars 9 are fixed in the respective bearing blocks 3 and supports 4 to be able to perform an axial motion. The sliding properties can be improved by the use of a selflubricating bearing liner 13, for example of plastics or carbon, in the bore of the bearing block 3 as well as by the use of similar bearing strata in the support block and retaining member 5 of the support 4.

Each retaining member surrounds a bar 9 in such a way as to permit axial and radial displacement of the cylinder 7 while preventing the cylinder 7 from being able to rotate about the fixed point in the guide rods 8.

A reversal of the support system described above is, of course, possible. That is, the rods and bars can be mounted on the casing 1 and the bearing blocks and supports can be mounted on the cylinder 7. The sliding stratum 13 may also be applied as an external stratum on the guide rods 8 or support bars 9, respectively.

In use, should the cylinder 7 expand or contract, or otherwise be subject to radial forces, the support bars 9 will slide radially of the casing l in the respective supports 4 in a plane passing through the fixed longitudinal axis defined by the guide rods 8.

What is claimed is:

1. In combination with a casing of an axial compressor and an adjusting cylinder, means for mounting said cylinder in said casing comprising at least one cylindrical guide rod secured to one of said casing and said cylinder axially of said casing,

a bearing block secured to the other of said casing and said cylinder and slidably receiving said guide rod therein axially of said guide rod to permit axial movement of said cylinder relative to said casing along a fixed longitudinal axis,

at least one support bar secured to one of said casing and said cylinder axially of said casing diammetrically opposite said guide rod, and

a support means secured to the other of said casing and said cylinder and slidably receiving said support bar therein axially of said support bar and radially of said casing to permit axial movement of said cylinder relative to said casing and radial movement of said cylinder relative to said casing in a plane passing through said fixed longitudinal axis.

2. The combination as set forth in claim 1 which further includes a self-lubricating bearing between at least one of said guide rod and bearing block and said support rod and said support.

3. The combination as set forth in claim 1 wherein said bearing block includes a cylindrical bore receiving said guide rod therein.

4. The combination as set forth in claim 1 wherein said support bar has a pair of oppositely disposed fiat surfaces and said support includes a support block having a flat bearing surface slidably receiving one of said flat surfaces of said support rod and a retaining member removably secured on said support block and having a fiat bearing surface slidably receiving the other of said flat support bar surfaces.

5. The combination as set forth in claim 4 wherein each bearing surface of said support block and said retaining member is a self-lubricating bearing.

l l= l 

1. In combination with a casing of an axial compressor and an adjusting cylinder, means for mounting said cylinder in said casing comprising at least one cylindrical guide rod secured to one of said casing and said cylinder axially of said casing, a bearing block secured to the other of said casing and said cylinder and slidably receiving said guide rod therein axially of said guide rod to permit axial movement of said cylinder relative to said casing along a fixed longitudinal axis, at least one support bar secured to one of said casing and said cylinder axially of said casing diammetrically opposite said guide rod, and a support means secured to the other of said casing and said cylinder and slidably receiving said support bar therein axially of said support bar and radially of said casing to permit axial movement of said cylinder relative to said casing and radial movement of said cylinder relative to said casing in a plane passing through said fixed longitudinal axis.
 2. The combination as set forth in claim 1 which further includes a self-lubricating bearing between at least one of said guide rod and bearing block and said support rod and said support.
 3. The combination as set forth in claim 1 wherein said bearing block includes a cylindrical bore receiving said guide rod therein.
 4. The combination as set forth in claim 1 wherein said support bar has a pair of oppositely disposed flat surfaces and said support includes a support block having a flat bearing surface slidably receiving one of said flat surfaces of said support rod and a retaining member removably secured on said support block and having a flat bearing surface slidably receiving the other of said flat support bar surfaces.
 5. The combination as set forth in claim 4 wherein each bearing surface of said support block and said retaining member is a self-lubricating bearing. 